Technical name for this stuff?

[Robert Jones]

Foil type material covering the under-floor area of a home built in 1949.

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[Tom Raymond]

Radiant barrier.

[Robert Jones]

Unusual to see in a crawl space. Mostly for attics right?

[Tom Raymond]

No. Heat radiates in all directions. It is designed to reflect radiant heat back too its source.

[Robert Jones]

Thanks Tom.

[Jim Katen]

Foil type material covering the under-floor area of a home built in 1949.

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49.46 KB

I see it mostly in homes that had electric radiant ceiling heat.

[Bill Kibbel]

It's not common here, but I see it in crawls more than attics.

I found one that was energized while crawling in mud with a sweat-soaked shirt.

[Nolan Kienitz]

It's not common here, but I see it in crawls more than attics.

I found one that was energized while crawling in mud with a sweat-soaked shirt.

Seems I recall Marc L. posting a study concerning radiant barrier being a pretty good conductor of electricity.

Not long after he posted that article I happened across an installation (radiant barrier in an attic) that could have been compromised electrically as well.

[Marc]

Download Attachment: Reflective-Radiant-Barriers-As-ignition-source.pdf

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Marc

[Tom Raymond]

Yes they can become energized. So can foil house wrap, foil faced insulation, metal flues, aluminum clad windows, steel doors, and brass door knobs.

In the early 90s I was working on a new subdivision when I encountered a house that was completely energized through those components. The blower switch on a fireplace insert contacted the chassis. A siding nail connected the aluminized house wrap to the flue pipe strapping. The fenestration was connected to the wrap via installation hardware.

[Marc]

Yes they can become energized. So can foil house wrap, foil faced insulation, metal flues, aluminum clad windows, steel doors, and brass door knobs.

In the early 90s I was working on a new subdivision when I encountered a house that was completely energized through those components. The blower switch on a fireplace insert contacted the chassis. A siding nail connected the aluminized house wrap to the flue pipe strapping. The fenestration was connected to the wrap via installation hardware.

Becoming energized isn't the issue. It's conductive surfaces that cannot carry lightening currents without getting hot enough to ignite combustible material.

Metallic flues, copper piping and such can, and do carry such currents and nothing happens because they can do it without harm.

CSST and radiant plywood are in the same category. Make the conductive component thicker or don't allow them in houses. Every climate has lightening.

Marc

[Tom Raymond]

Fire is a high probability outcome from a lightening strike regardless of the components. If that outcome is the basis of your concern you should be pushing for codifying lightening suppression. Removing all conductive components and living in sod huts still presents the possibility of fire resulting from lightening strikes.

Personally, I think the odds of a lightening strike are similar to the odds of one stray wire and one errant nail conspiring to place 120 volts across a doorknob.

[Bill Kibbel]

Lightening - the process of making something lighter in weight, color, brightness or mood.

Lightning - the flashy stuff in the sky followed by loud booms. It could also be greased in the '50s and '60s.

[Tom Raymond]

Homophobia - the fear of using the wrong homonym.

There's no reason to be scared. Some helpful chap will come along and correct you.

[Bill Kibbel]

Homophobia - the fear of using the wrong homonym.

I guess that would be funny if lightening and lightning were homonyms.

[Chad Fabry]

Homophobia - the fear of using the wrong homonym.

I guess that would be funny if lightening and lightning were homonyms.

I think they pass for homophones so the word play is still funny.

[Les]

Homophobia - the fear of using the wrong homonym.

I guess that would be funny if lightening and lightning were homonyms.

I think they pass for homophones so the word play is still funny.

me two, tu, to, too, tou, tue,

[Nolan Kienitz]

OK ... y'all prompted me a bit of a diversion (as I'm wont to do ... ) [^]

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Mayfield, OK is the rig's location ... FYI

[kurt]

Homophobia - the fear of using the wrong homonym.

There's no reason to be scared. Some helpful chap will come along and correct you.

That's funny, regardless.

[Chad Fabry]

OK ... y'all prompted me a bit of a diversion (as I'm want to do ... ) [^]

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Mayfield, OK is the rig's location ... FYI

Ha!, I get it!

[kurt]

I want, as is my wont.

[Jim Baird]

I wondered when the spelling monitor would catch this one.

Lightening - the process of making something lighter in weight, color, brightness or mood.

Lightning - the flashy stuff in the sky followed by loud booms. It could also be greased in the '50s and '60s.

Now here is one from a state where education has been getting the small change lately.

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[Rob Amaral]

No wonder I see so many spelling errors on CNN..

[rjbrown2]

Spelling in a non-phonetic, poly sourced language like American English is not correlated with the intelligence of the writer.

There are some fanciful quotes variously attributed to Jefferson, Mark Twain, et al about the narrowness of people who can only think of one way to spell a word. I liken spelling to good table manners, like not belching loudly after the meal, or wiping your mouth on your sleeve...

[Trent Tarter]

I see this quite often in crawlspaces in 50's built homes. I call it "old reflective foil' or "foil radiant barrier".